Variable speed power transmission

ABSTRACT

A continuously variable speed power transmission includes a rotatable input member, a rotatable output member including a plurality of rearwardly directed output face cams. A reaction control rotor selectively rotatable about the input axis includes a plurality of forwardly directed reaction face cams opposed to the output face cams. A pericyclic motion converter rotatably mounted for nutational motion about the input axis includes a plurality of load transmitting follower members simultaneously engageable with the output face cams and with the reaction face cams. A control mechanism selectively adjusts the rotational rate of the reaction control rotor relative to the input member such that relative rotation between the reaction control rotor and the input member results in both rotation and nutation of the pericyclic motion converter about the input axis resulting in a continuously variable change of ratio of the rotational speed of the output member relative to the input member.

The present application is related to now abandoned ProvisionalApplication Serial No. 60/170,785 of Alphonse J. Lemanski, filed Dec.15, 1999, entitled “Variable Speed Power Transmission”, based on whichpriority is herewith claimed under 35 U.S.C. §119(e) and the disclosureof which is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to power transmission systems and, moreparticularly, to such systems which are of the all rolling, positivecontacting, variable speed type and, still more particularly, whereinextensive load sharing occurs among the load transmitting members.

2. Prior Art

The present invention relates to a transmission system whichincorporates oscillator members. It is known in the art to use awobbling member known as a nutator to effect a fixed gear reduction orspeed reduction/increase in a transmission system. Generallyrepresentative of the pertinent prior art as it pertains to the presentinvention are a trio of U.S. Patents, namely, U.S. Pat. No. 4,620,457 toDistin et al., U.S. Pat. No. 3,590,659 to Maroth, and U.S. Pat No.1,748,907 to Vallance.

U.S. Pat. No. 4,620,457 to Distin et al. discloses a torque transmittinggearing system of the nutating type equipped with a nutating idlermember which is in torque transmitting engagement with both a stator andan output gear. Torque transmission between the respective elements isachieved via respective series of rolling, torque transmitting elementsin the form of tapered rollers. The rollers are maintained insubstantially continuous contact with both their respective driving anddriven raceway surfaces, which are formed with trochoidal curvature.Within a given pair of coacting gear surfaces, one surface is shapedwith epitrochoidal curvature, and the other with hypotrochoidalcurvature.

U.S. Pat. No. 3,590,659 to Maroth discloses a speed changer apparatuswith a nutating member having force transfer members in the form ofroller elements which nutatively contact inclined surfaces on an actionmember coupled to an output shaft. The nutating member is prevented fromrotation by stationary mounted inclined surfaces which are contacted byforce transfer members/The nutating member is peripherally engaged by arotating driving member coupled to a rotating input shaft. The drivingmember is provided with a surface shaped to impart nutative motion tothe nutating member. Superior axial balance is obtained by operating apair of nutating sections with opposing axial motions with respect toeach other.

U.S. Pat. No. 1,748,907 to Vallance discloses apparatus for transmittingrotary motion from one rotatable element to another rotatable elementusing a plate, ring, or similar component connected to the rotatableelements using such a construction that rotation of one of the elementscauses the plate, ring, or similar component to tilt or oscillate insuch a manner that every point in its circumference moves in alemniscate path and effects rotation of the other one of the elements atan invariable reduced speed or at an invariable increased speed. Ingreater detail, the Vallance patent discloses a speed reductionmechanism in the form of a nutating gear system, wherein an input shaftinitiates wobbling motion of an intermediate member 7, via theengagement of a portion 9 b of the intermediate member with an angled orcanted portion of the input shaft 2. Radially outwardly on the member 7are disposed a train of teeth 10 which engage stator teeth 11 formed ona portion of the stationary housing 5. Inside of the cup-member 7 arearranged a number of hemispherical recesses 7 b, in which are fixedlyseated a like number of balls 8. These balls are in turn in engagementwith a continuous curved groove 6 b formed in an output member 6. Aswith other known nutating systems, the engagement between stator teeth10, 11 prevents the intermediate member 7 from rotating during nutation,so that output rotation is effected solely by means of the engagementbetween the fixed balls and the groove. As the idler member 7 nutates,the balls 8 successively cam the element 6 rotationally by engaging thewalls of the curved groove.

It was with knowledge of the foregoing state of the technology that thepresent invention has been conceived and is now reduced to practice.

SUMMARY OF THE INVENTION

The present invention discloses, in one embodiment, a continuouslyvariable speed power transmission includes a rotatable input member, arotatable output member including a plurality of rearwardly directedoutput face cams thereon. A reaction control rotor mounted for selectiverotation about the input axis includes a plurality of forwardly directedreaction face cams thereon in opposition to the output face cams on theoutput member. A pericyclic motion converter rotatably mounted fornutational motion about the input axis includes a plurality of loadtransmitting follower members thereon simultaneously engageable with theoutput face cams and with the reaction face cams. A control mechanismselectively adjusts the rate of rotation of the reaction control rotorrelative to the input member such that relative rotation between thereaction control rotor and the input member results in both rotation andnutation of the pericyclic motion converter about the input axis andthereby results in a continuously variable change of ratio of therotational speed of the output member relative to the input member. Inanother embodiment, the pericyclic motion converter is rotatably mountedon an encompassing housing. In either event, the load transmittingmembers of the pericyclic motion converter kinematically under purerolling contact traverse a mathematically higher order spherical path ofaction during each revolution of the input member.

The present invention is an all rolling positive contacting mechanicalvariable speed, power transmission system. It utilizes the fundamentalprinciples of high load capacity and torque transmission efficiencyfacilitated by high precision rolling element bearings. The concentratedrolling surface contact conditions that prevail in the present inventionduring torque transmission also facilitates its operation with minimalfluid lubricant. The unique design of conjugate load bearing surfaces inthe present invention permits the use of tribologically robust materialsand surface film transfer conditions to take place in the concentratedroller contacts. All other known mechanical power transmission systemsthat employ nutation and various types of gearing arrangements, ballsand rollers which engage face cam tooth type surfaces do not possess theunique concentrated rolling conjugate surface contact conditions thatare incorporated in the present invention. The present invention isthereby capable of much higher torque density and power transmissionefficiency than other known continuously variable mechanical powertransmission systems.

The transmission of the invention can be employed in many devices andincludes an input member, reaction members driven by the input member, apericyclic member or oscillator member driven by the input member and adrive output member driven by the pericyclic member, in which therotation speed of the reaction member and or the pericyclic member canbe controlled independent of the input member: thereby, allowing thespeed reduction/increase at the output drive member to vary. Morespecifically, the invention is an all rolling positive contactingmechanical variable speed, power transmission system. It utilizes thefundamental principles of high load capacity and torque transmissionefficiency of high precision rolling element bearings. The concentratedrolling surface contact conditions that prevail in the present inventionduring torque transmission facilitates its operation with minimal fluidlubricant. The unique design of conjugate load bearing surfaces in thepresent invention permits the use of tribologically robust materials andsurface film transfer conditions to take place in the concentratedroller contacts. All other mechanical power transmission systems thatemploy various types of gearing arrangements, balls or rollers whichengage face cam tooth type surfaces do not possess the uniqueconcentrated rolling conjugate surface contact condition that isincorporated in the present invention. The present invention is therebycapable of higher torque density and power transmission efficiency thanother mechanical power transmission systems.

A primary feature, then, of the present invention is the provision of avariable speed power transmission which not only produces a certain gearreduction or speed reduction/increase in a transmission using such anoscillator member but which operates to vary the gear reduction or speedreduction/increase in the transmission.

Another feature of the present invention is the provision of such atransmission which results in a continuously variable change of ratio ofthe rotational speed of the output member relative to the input member.

Yet another feature of the present invention is the provision of such apower transmission which includes an input member rotatable about aninput axis, an output member rotatable about an output axis including aplurality of rearwardly directed output face cams thereon, a reactioncontrol rotor mounted for selective rotation about the input axisincluding a plurality of forwardly directed reaction face cams thereonin opposition to the output face cams on the output member, a pericyclicmotion converter rotatably mounted for nutational motion about the inputaxis including a plurality of load transmitting follower members thereonsimultaneously engageable with the output face cams and with thereaction face cams, and an active control device for selectivelyadjusting the rate of rotation of the reaction control rotor relative tothe input member whereby relative rotation between the reaction controlrotor and the input member results in both rotation and nutation of thepericyclic motion converter about the input axis and thereby results ina continuously variable change of ratio of the rotational speed of theoutput member relative to the input member.

Still another feature of the present invention is the provision of sucha power transmission in which the output face cams, the reaction facecams, and the follower members of the pericyclic motion converter allemploy bevel type gear teeth including internal bevel type gear teethhaving a pitch angle greater than 90°.

Yet a further feature of the present invention is the provision of sucha transmission having the construction of the pericyclic motionconverter being rotatably mounted on an encompassing housing.

Still another feature of the present invention is the provision of sucha transmission in which the load transmitting members of the pericyclicmotion converter kinematically under pure rolling contact traverse amathematically higher order spherical path of action during eachrevolution of the input member.

Other and further features, advantages, and benefits of the inventionwill become apparent in the following description taken in conjunctionwith the following drawings. It is to be understood that the foregoinggeneral description and the following detailed description are exemplaryand explanatory but are not to be restrictive of the invention. Theaccompanying drawings which are incorporated in and constitute a part ofthis invention, illustrate one of the embodiments of the invention, andtogether with the description, serve to explain the principles of theinvention in general terms. Like numerals refer to like parts throughoutthe disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and other features of the present invention areexplained in the following description, taken in connection with theaccompanying drawings, wherein:

FIG. 1 is a side elevation view, in section, of one embodiment of thecontinuously variable power transmission of the present invention;

FIG. 2 is a perspective view, largely cut away and in section,illustrating the internal components of the power transmissionillustrated in FIG. 1;

FIG. 3 is a side elevation view, in section, similar to FIG. 1, butillustrating this embodiment of the invention in greater detail,specifically showing multi-roller contacts occurring simultaneously atdiametrically opposite quadrants of the invention;

FIG. 4 is a diagrammatic view of a model for deriving pertinentinformation relating to the pericycler unit;

FIG. 5 is a graph depicting the path along which the center of afollower member of a pericyclic motion converter moves during a onerevolution traverse while in engagement with the reaction control rotoras plotted for a plurality of values of pericyclic angle gamma;

FIG. 6 is a cross sectional view in elevation of a prototype design ofthe present invention that is typical for mounting in a wheel hub of avehicle;

FIG. 7 is a graph of calculated, and four measured data points, of theoutput speed ratio V as a function of the reaction member speed ratioR_(rm);

FIG. 8 is an exploded perspective view, partially cut away and shown insection, of another embodiment of the continuously variable powertransmission of the present invention;

FIG. 9 is a detail elevation view illustrating an output disk which is acomponent of the power transmission illustrated in FIG. 8;

FIG. 10 is a detail side elevation view of the component illustrated inFIG. 9;

FIG. 11 is a detail elevation view illustrating a reaction control rotorwhich is a component of the power transmission illustrated in FIG. 8;

FIG. 12 is a detail side elevation view of the component illustrated inFIG. 11;

FIG. 13 is a detail elevation view illustrating a reaction control rotorwhich is a component of the power transmission illustrated in FIG. 8;

FIG. 14 is a detail side elevation view of the component illustrated inFIG. 13;

FIG. 15 is a detail elevation view, in section, of a pericyclic motionconverter which is a component illustrated in FIG. 8;

FIG. 16 is an exploded perspective view, partially cut away and shown insection, of still another embodiment of the continuously variable powertransmission of the present invention; and

FIG. 17 is a detail elevation view, in section, of a modified pericyclicmotion converter which is a component illustrated in FIG. 16.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIGS. 1, 2, and 3, there is shown by means of crosssectional views, one embodiment 10 of a variable power transmissionincorporating features of the present invention. Although the variablepower transmission concept of the invention will be described withreference to the embodiments shown in the drawings, it should beunderstood that the present invention can be embodied in many alternateforms or embodiments. In addition, any suitable size, shape or type ofelements or materials could be used

The variable speed power transmission 10 includes a rotatable splitpower pericyclic motion converter retaining ring member 11 journaled tothe upper housing 15 a that is attached to an input drive shaft 12 of aprime mover (not shown), via a bevel gear set 13 or face gear set (notshown), a rotatable coaxial reaction control rotor 14 a connected to thelower stationary housing 15 b via a pair of rolling element bearings 16a and 16 b, a coaxial driving member 17 connected to the output shaft18, and a stationary coaxial reaction member 14 b connected to astationary cover 15 c. The pericyclic retaining ring member 11 embodiesa set of two journaled concentric ring assemblies 19 and 20 with innerand outer rings separated by spoke pins 21 equally spaced such that eachembodies an outer roller 22 and an inner roller 23. These two sets ofpericyclic motion converter ring assemblies 19 and 20 that incorporateequally spaced spoke type pins 21 with outer rollers 22 and innerrollers 23, are journaled to the pericyclic motion converter retainingring member 11 at a calculated design coning angle to achieve nutationmotions.

In high load capacity and higher speed drive train systems, “splitpower” transmissions are typically designed to facilitate increasedpower density by providing a dual torque/load path from a prime mover tothe output member (usually an output shaft) that drives the final systemunit. Such a design is dimensionally more compact than conventionaldesigns. The split power design configuration also provides anadditional benefit to nutational types of transmissions by eliminating apair of counter weights that would be necessary to eliminate dynamicimbalance caused by the nutational motion of the pericyclic motionconverter due to its mounting arrangement, that is, at a design coningangle to the input shaft center line. Although the pericyclic motionconverter is statically balanced, dynamic thrust forces develop due tomoment loads created by the nutational motion. However, the split powerdesign overcomes the dynamic imbalance via thrust force cancellation.

The two reaction members 14 a and 14 b are designed as circularfaceplates that incorporate equally spaced individual conjugateconvoluted type roller raceways 28 a and 28 b around their periphery tofacilitate the reaction of contact forces during each pericyclic path ofaction of the two pericyclic motion converter ring assemblies 19 and 20.The driving member 17 is also designed as a circular faceplate withindividual conjugate convoluted type roller raceways 30 a and 30 b (FIG.2) around its periphery to achieve torque transmission at variabledesign speeds of the output shaft 18. The unique individual convolutedand enveloping conjugate roller raceways cams 28 a and 28 b and 30 a and30 b, respectively, around the periphery of the reaction members 14 aand 14 b and the dual face cam driving member 17 are designed tokinematically and dynamically take advantage of the inherent high loadcapacity and efficiency of high precision rolling element bearings.

The flexible component arrangements of the present invention make itfeasible to infinitely vary its speed ratio capability and make aselection of different individual speed ratios with the same components.This capability is made possible by changing the effective difference inangular raceway spacing (or angular positioning) between the driving andreaction members 17 and 14 a and 14 b via an actuator controller. Theoperation of the variable speed power transmission 10 is as follows: theinput drive shaft 12 rotates the pericyclic motion converter retainingring member 11 via a bevel gear set 13 to permit nutation or oscillatorytype motion of the two pericyclic motion converter ring assemblies 19and 20 via roller-raceway engagement with reaction control rotor members14 a and 14 b and simultaneous roller-raceway engagement with the outputdriving member raceways 17 resulting in the conversion of nutation typemotion to rotary motion of the output shaft 18. Different speed ratiosat the output shaft 18 can be achieved by adjusting the rotational speedof the reaction control rotor member 14 a.

It is envisioned that the oscillator arrangements in the pericyclicmember 11 could be replaced by a single oscillator arrangement. It isenvisioned that the principles of this invention can be employed in manydevices, namely having an input member, a reaction member driven by theinput member, a pericyclic member or oscillator member driven by theinput member and a drive member driven by the pericyclic member, inwhich the rotation speed of the reaction member and or the pericyclicmember can be controlled independent of the input member; thereby,allowing the speed reduction/increase at the drive member to vary. It isalso envisioned that the drive member can rotate in a direction oppositeof the input member and that the drive member can be placed in acoasting or neutral position so that there is not translation of energyfrom the input member.

Consider now the kinematics of the variable speed power transmissionconcept of the present invention. The split power pericyclic assembly 11embodies a set of two journaled concentric ring units 19, 20 separatedby a selected number of equally spaced spoke type pins 21 that eachjournal an outer roller 22 and inner roller 23. The two ring units 19,20 are journaled to the rotatable pericyclic ring member 11 at acalculated design coning angle to facilitate oscillatory or wobble typemotion of ring units 19, 20. The reaction member 14 a, which isjournaled to the housings, is designed as a circular face plate thatincorporates a selected number of equally spaced conjugate convolutedroller raceways 28 a around its periphery to facilitate the reaction ofcontact forces during each pericyclic path of action. The output drivingrotor member 17 which is connected to the output shaft 18 is designed asa double circular faceplate with back to back convoluted type rollerraceways 30 a, 30 b around its periphery to provide rotary torquetransmission at design speeds of the output shaft 18. The stationaryreaction member 14 b which is attached to the housing is also designedas a circular face plate that incorporates a selected number of equallyspaced conjugate convoluted roller raceways 28 b around its periphery tofacilitate the reaction of contact forces during each pericyclic path ofaction.

Rotation of the input shaft 12 causes oscillatory or wobble type motionof the journaled pericyclic ring units 19, 20 that embody outer rollers22 and inner rollers 23. The pericyclic ring unit rollers simultaneouslyengage a full quadrant of the reaction members 14 a, 14 b and a fullquadrant of the output driving rotor member 17. More specifically, theinner rollers 23 engage the reaction member 14 a and the outer rollers22 engage the output driving rotor 17. In this manner, the transmittedload is shared by fifty percent (two quadrants) of the rollers and theconjugate convoluted roller raceways 28 a, 30 a and 28 b, 30 brespectively as shown in FIG. 2. As a result of the unusualkinematic/kinetic features of the pericycler, the rotation of the inputshaft 12 relative to the reaction members 14 a, 14 b causes adifferential motion of the output driving rotor member, therebypermitting controlled variable speed without any significant power loss.

The geometry of the conjugate convoluted roller raceways 28 a, 28 b and30 a, 30 b (FIG. 2) is determined from the path of motion of a fixedpoint on the pericycler ring units as the input shaft rotates thejournaled split power pericyclic assembly member 11 and the rollers 22and 23 engage the reaction members 14 a, 14 b thereby driving the outputdriving rotor member 17. One 360 degree rotation of the input shaft 12results in one complete spherical pericyclic path of action. Thefollowing kinematic treatment determines the angular velocities of theinput shaft 12 and the pericycler ring units and ultimately defines theconjugate convoluted roller raceways of the reaction members and theoutput driving rotor member 17.

Three sets of right-handed orthogonal unit triads are shown in FIG. 4.FIG. 4 is a diagrammatic representation of a model for deriving theangular velocity of the pericycler and its position as a function ofinput shaft rotation to establish the path of a fixed point in thepericycler which defines the spherical path along which it moves duringone raceway traverse on the reaction member. The coordinates formachining the reaction and output rotor face cams are also establishedfrom this model.

The triad ({right arrow over (I)},{right arrow over (J)},{right arrowover (K)}) is fixed in space and denotes the inertial frame while thetriads({right arrow over (i)}_(s),{right arrow over (j)}_(s),{rightarrow over (k)}_(s)) and ({right arrow over (i)},{right arrow over(j)},{right arrow over (k)}) are respectively fixed in the input shaftand pericycler. Transformation from one set of coordinates to the otheris accomplished by defining the three conventional Euler angles (φ,φ,Ψ)[2]. The resulting orthogonal transformation matrix is: $\begin{matrix}{\left\lbrack {E\left( {\varphi,\theta,\psi} \right)} \right\rbrack = \begin{bmatrix}{{- \sin}\quad {\varphi sin}\quad \psi} & {\cos \quad \varphi \quad \sin \quad \psi} & {{- \sin}\quad \theta \quad \cos \quad \psi} \\{{+ \cos}\quad \theta \quad \cos \quad \varphi \quad \cos \quad \psi} & {{+ \cos}\quad \theta \quad \sin \quad \varphi \quad \cos \quad \psi} & \quad \\{{- \sin}\quad \varphi \quad \cos \quad \psi} & {\cos \quad \theta \quad \cos \quad \psi} & {\sin \quad \theta \quad \sin \quad \psi} \\{{- \cos}\quad {\theta cos}\quad \varphi \quad \sin \quad \psi} & {{- \cos}\quad \theta \quad \sin \quad \varphi \quad \sin \quad \psi} & \quad \\{\sin \quad \theta \quad \cos \quad \varphi} & {\sin \quad \theta \quad \sin \quad \varphi} & {\cos \quad \theta}\end{bmatrix}} & (1)\end{matrix}$

and the relevant transformation is

{right arrow over (r)}=[E(φ,θ,Ψ)]{right arrow over (R)}  (2)

where {right arrow over (R)} is the vector in the fixed frame ({rightarrow over (I)},{right arrow over (J)},{right arrow over (K)}) and{right arrow over (r)} denotes the components in the moving system({right arrow over (i)},{right arrow over (j)},{right arrow over (k)}).

In order to determine the path of a point fixed in the pericycler it isnecessary to define angular velocity of the pericycler and representthis velocity in terms of φ,θ,Ψ, and their derivatives. Finally, theresulting equations may be integrated to obtain the pericycler positionas a function of input shaft rotation. If the ratio of the number ofconvoluted raceways on the reaction members to the number of rollers onthe pericycler is λ, then the angular velocity of the pericyclerrelative to the shaft in the shaft frame is clearly

{right arrow over (ω)}_(ns) ^(s)=λω_(reac.){right arrow over (k)}_(s)

where ω_(reac.) is the angular velocity of the reaction members withrespect to the shaft. When the reaction members are stationary and theshaft has an absolute angular velocity {right arrow over (ω)}_(s){rightarrow over (K)}, then

 {right arrow over (ω)}_(ns) ^(s)=−λω_(s){right arrow over (k)}_(s)  (3)

Since the shaft frame is located by shaft rotation α and the pericyclerangle γ, the above may be transformed in the inertial frame with φ=α,θ=γ, Ψ=0.

{right arrow over (ω)}_(ns)=[E(α,γ,0)]^(T){right arrow over (ω)}_(ns)^(s)=−ω_(s)λsinγcosα{right arrow over (I)}−ω_(s)γsin γsinα{right arrowover (J)}−ω_(s)λcosγ{right arrow over (K)}  (4)

The absolute pericycler and shaft velocities are thus respectivelywritten as

{right arrow over (ω)}=−ω_(s)λsinγcosα{right arrow over(I)}−ω_(s)λsinγsinα{right arrow over (J)}+ω_(s)(1−λcosγ){right arrowover (K)}ω_(s)=ω_(s){right arrow over (K)}  (5)

In terms of φ,θ,Ψ, the angular velocity of the pericycler is expressedas

{right arrow over (ω)}_(n)=φ{right arrow over (K)}+θ{right arrow over(j)}_(s)+Ψ{right arrow over (k)}  (6)

where “·” denotes the time derivatives and the unit vectors {right arrowover (j)}_(s) and {right arrow over (k)} are expressible in terms of({right arrow over (I)},{right arrow over (J)},{right arrow over (K)})and (φ,θ,Ψ) as shown in FIG. 4. Some algebraic manipulation results in$\begin{matrix}{\begin{Bmatrix}\overset{.}{\varphi} \\\overset{.}{\theta} \\\overset{.}{\psi}\end{Bmatrix} = {\begin{bmatrix}{{- \cos}\quad \varphi \quad \cot \quad \theta} & {{- \sin}\quad \varphi \quad \cot \quad \theta} & 1 \\{{- \sin}\quad \varphi} & {\cos \quad \varphi} & 0 \\{\cos \quad \varphi \quad \cos \quad {ec}\quad \theta} & {\sin \quad \varphi \quad \cos \quad {ec}\quad \theta} & 0\end{bmatrix}\begin{Bmatrix}\omega_{n_{1}} \\\omega_{n_{2}} \\\omega_{n_{3}}\end{Bmatrix}}} & (7)\end{matrix}$

where the notation {right arrow over (ω)}_(n)=ω_(n) ₁ {right arrow over(I)}+ω_(n) ₂ {right arrow over (J)}+ω_(n) ₃ {right arrow over (K)} isused.

If the shaft angular velocity ω_(s){right arrow over (K)} is a constant,then Equations (5) and (7) may be combined to give the final expressionsfor φ,θ,Ψ in terms of shaft rotation α. $\begin{matrix}\begin{matrix}{\frac{\varphi}{\alpha} = {{\lambda \quad \sin \quad \gamma \quad \cot \quad \theta \quad {\cos \left( {\alpha - \varphi} \right)}} - {\lambda \quad \cos \quad \gamma} + 1}} \\{\frac{\partial}{\alpha} = {{- \lambda}\quad \sin \quad \gamma \quad \sin \quad \left( {\alpha - \varphi} \right)}} \\{\frac{\psi}{\alpha} = {{- \lambda}\quad \sin \quad \gamma \quad \cos \quad {ec}\quad \theta \quad \cos \quad \left( {\alpha - \varphi} \right)}}\end{matrix} & (8)\end{matrix}$

In general these equations may be integrated with the initial conditionsα=0→φ=0, θ=γ, Ψ=0. However, since {right arrow over (ω)}^(s) _(ns) isalong the unit vector {right arrow over (k)}_(s) the pericycler vector{right arrow over (k)} is fixed also in the shaft, which means that θ=γ,a constant, i.e., dθ/dα=0. A substitution of these conditions inEquation (8) gives

φ=α

θ=γ  (9)

Ψ==λα

As an application of the above analysis, let the point on thepericycler, under condition, have a position vector {right arrow over(r)} in the pericycler frame

{right arrow over (r)}=cos β{right arrow over (i)}−sin β{right arrowover (k)},

β being a coning angle.

It is clear that such a point will move on a sphere of unit radius andwill be located by a position vector R in the inertial frame by theequation

{right arrow over (R)}=[E(α,γ,−λα)]^(T){right arrow over (r)}  (10)

The components of {right arrow over (R)}=R₁{right arrow over(I)}+R₂{right arrow over (J)}+R₃{right arrow over (K)} may betransformed into conventional longitudes and latitudes denotedrespectively as $\begin{matrix}\begin{matrix}{\xi = {- {\tan^{- 1}\left( \frac{R_{2}}{R_{1}} \right)}}} \\{\eta = {\tan^{- 1}\left( \frac{R_{3}}{\sqrt{R_{1}^{2} + R_{2}^{2}}} \right)}}\end{matrix} & (11)\end{matrix}$

For β=10° and λ=18/19, i.e., 18 raceways on the reaction members meshingwith 19 rollers on the pericycler, ξ and η are plotted for variousvalues of pericycler angle γ in FIG. 5. These profiles actually denotethe path along which the center of a roller will move during one racewaytraverse on the reaction members.

A prototype design of the present invention, as seen in FIG. 6 has beenfabricated and tested to verify its capability to function as a steplessvariable speed transmission. This prototype PVT (Pericyclic VarydriveTransmission) is an example of its application to human powered vehiclesincluding bicycles, scooters, wheel chairs, carts, etc. and forpower-assisted human powered vehicles utilizing electric motors andcontrol electronics to augment the user's effort. This prototype PVT canbe mounted inside the hub of a bicycle rear wheel to facilitate steplessspeed changes over a ratio range of about 0.535 to about 4.457. Withsuch a construction, the PVT will likely eliminate the state-of-the-artderailleur/multi-sprocket system that permits only a relatively few stepratio speed changes.

The prototype PVT comprises a pericyclic member 5 journaled to the inputshaft 2 at a designed angle 7 to permit oscillatory motion and therebycontinuous torque transmitting engagement with a journaled reactionmember 3 and simultaneously with an output driving member 4. For thebicycle application, the input speed is augmented, that is, increased,by a planetary gear set 9 having, for example, a 6:1 ratio. Thepericycler member embodies a set of equally spaced rollers 6 that meshwith the convoluted type raceways of the reaction member 3 and theoutput driving member 4.

The output speed of the PVT can be varied by changing the reactionmember 3 rotational speed with respect to the input shaft rpm. Maximumoutput speed is designed to decrease proportionately with increasingreaction member speed. The reaction member is counter rotating, that is,its rotation is in the opposite direction with respect to the inputrotation.

To facilitate application in which the designs require low speed ratioranges such as 0.5:1 to 5.6:1 which is typical for bicycles, anaugmentation member is used to increase the basic input ratio toapproximately 10:1. This provides an efficient rate of rotation of thereaction control rotor relative to the input member for a designvariable speed output range of 0.5:1 to 5.6:1. The augmentation membercan be a planetary gear or other in-line mechanical gear member.

The PVT design features that influence the output speed are as follows:

Number of reaction member raceways, Nrm  8 Number of output drivingmember raceways, Nom 10 Number of pericyclic rollers, Npr  8 Planetaryspeed increase ratio, Rpl  6:1

The reaction member speed ratio (Rpl) is defined as the ratio ofreaction member speed rotation and the PVT input speed. The variableoutput speed ratio (V), (ratio of output speed to the input speed) iscalculated by the following equations:

M=(Nom×Npr)/(Nom×Npr−Npr×Nrm)

where M is the maximum PVT ratio of input to output with the reactionmember fixed; and

V=Rpl×(1+Rm×[M−1])/M.

FIG. 7 is a graph of calculated output speed ratio V as a function ofthe reaction member speed ratio Rrm, and shows the linearly variableoutput speed capability of the prototype PVT unit.

The variable output speed capability of the prototype PVT unit wasverified by measuring the rotational speeds of the input shaft 2,reaction member 3 and the output driving member 4. The component memberspeeds were measured by timing each member for a selected number ofrotations (that is, by measuring the time required for 30 revolutions ofthe input shaft 2, 10 revolutions of the reaction member 3 and 60revolutions of the output driving member 4. The reaction member 3 speedwas increased progressively from zero up to a maximum speed that couldbe visually counted. Thus, various component rotational speeds weremeasured for four separate speed settings of the reaction member 3. Ateach of these speed settings, three measurements were made to minimizepotential errors. Table 1 summarizes the measured times in seconds androtational speeds in rpm for the respective components. Table 1 alsoshows the speed ratios of the reaction member (Rrm) and the overalloutput ratios for the respective measurements.

Table 2 compares the calculated and measured output ratios as a functionof the ratios Rrm for the reaction member 3. As shown in FIG. 7, themeasured data corresponds very closely with the calculated values of theoutput ratios for the speed settings of the four reaction members 3evaluated.

TABLE 1 Measured Times and Speeds of PVT Input Member, Reaction Member,and Output Member Input Member Speed Reaction Member Speed Output MemberSpeed 30 Rev. Time RPM 10 Rev. Time RPM R_(RM) Ration 60 Rev. Time RPMOutput I. 15.39 116.959 — 0 0.000 25.48 141.287 1.208 15.34 117.340 — 00.000 25.60 140.625 1.198 15.35 116.883 — 0 0.000 25.55 140.900 1.205II. 15.69 114.723 18.55 −32.345 −0.047 32.37 111.214 0.969 15.70 114.65018.46 −32.503 −0.047 32.04 112.360 0.980 15.56 115.681 18.64 −32.189−0.046 31.85 113.030 0.977 III. 15.30 117.647 10.02 −59.880 −0.085 38.4593.62 0.796 15.35 117.264 9.96 −60.241 −0.086 38.28 94.044 0.802 15.33117.417 10.01 −59.940 −0.085 38.26 94.093 0.801 IV. 15.47 116.354 8.72−68.807 −0.099 42.98 83.760 0.720 15.38 117.035 8.30 −72.289 −0.10342.98 83.760 0.716 15.44 116.580 8.54 −70.258 −0.100 42.69 84.329 0.723

TABLE 2 Average Speed Ratios Reaction Output to Input Ratio MemberCalculated R_(RM) Ratio Measured I. 0.000 1.200 1.204 II. −0.047 0.9740.976 III. −0.085 0.792 0.800 IV. −0.101 0.715 0.714 Notes 1. R_(rm)Ratio is the ratio of reaction member speed to the input speed. 2.Output ratio is the ratio of output speed to the input speed.

In conclusion the variable stepless output speed capability of theprototype PVT unit was verified. The output speed ratio varies linearlywith increasing ratio Rrm for a reaction member 3 from a maximum outputspeed for a stationary (Rrm=0) reaction member 3. The output speeddecreases linearly.

Turn now to FIGS. 8-17 for the description of another embodiment of theinvention. In this instance, beginning with FIGS. 8-10, a continuouslyvariable speed power transmission 200 includes an input member 202 inthe form of longitudinally extending drive shaft 204 rotatable about aninput axis 206. An output member 208 includes a longitudinally extendingdriven shaft 210 and an integral output disk 212 lying generally in aplane perpendicular to an output axis 214 about which driven shaft 210rotates. The output disk 212 includes a solid web 213 which is splinedor otherwise fixed to the driven shaft 210 and extends between a hub 216fixed on the driven shaft and an outer peripheral flange 218 lying in aplane parallel to the output axis containing a plurality of rearwardlydirected output face cams 220.

Viewing now FIGS. 8, 11, and 12, a reaction control rotor 222 is mountedfor selective rotation about the input axis 206. The reaction controlrotor 222 includes an input disk or web member 224 lying in a planeperpendicular to the input axis and extending between a hub 226rotatably mounted on the drive shaft 204 and an outer peripheral flange228 lying in a plane parallel to the input axis containing a pluralityof forwardly directed reaction face cams 230 positioned in opposition tothe output face cams 220 on the output member 208.

In a modified embodiment of the invention illustrated in FIGS. 13 and14, a reaction control rotor 222 a may include a hub 226 a fixed on adriven shaft 204 a, an outer peripheral flange 228 a lying in a planeparallel to the output axis and containing a plurality of forwardlydirected reaction face cams 230 a, and a plurality of radially extendingspokes 232 at circumferentially spaced locations extending between andintegral with the hub 226 a and with the outer peripheral flange.Although not illustrated, the output disk 212 may be similarly modifiedto include a plurality of radially directed spokes in place of the solidweb member 213.

With continued reference to FIG. 8 and now turning also to FIG. 15, theinput member 202 is seen to include the longitudinally extending driveshaft 204 and a canted cam member 234 fixed on the drive shaft as by akey member 236. The canted cam member 234 has a first bearing track 238and a cam axis 240 coplanar with the input axis 206 but angularlydisposed relative to the input axis. The power transmission 200 furtherincludes a pericyclic motion converter 242 which itself includes aperipheral ring 244 coplanar and coaxial with the canted cam member 234and an intermediate ring 246 coplanar and coaxial with the canted cammember and having a second bearing track 248 spaced from and opposed tothe first bearing track. In a customary fashion, bearing elements 250are suitably received between and are engaged with the first and secondbearing tracks 238, 248 enabling rotation of the intermediate ring aboutthe canted cam member.

A plurality of radially extending follower pins 252 are fixed atcircumferentially spaced locations extending between and integral withthe peripheral ring 244 and with the intermediate ring 246 and a loadtransmitting follower member 254 such as a roller is rotatably mountedon each of the follower pins. As clearly seen in FIG. 15, a plurality ofthe load transmitting follower members 254 simultaneously engage atdiametrically opposite locations with the output face cams 220 and withthe reaction face cams 230.

Suitable control apparatus in the form of a central processor unit 256is an integral and necessary part of the invention and serves toselectively adjust the rate of rotation of the reaction control rotor222 relative to the input member or drive shaft 204. In one instance,the reaction control rotor 222 may be fixed for unitary rotation withthe drive shaft and in other instances may rotate through a desiredrange of rates of rotation relative to the input shaft. In thoseinstances in which relative rotation occurs between the reaction controlrotor 222 and the drive shaft 204, both rotation and nutation of thepericyclic motion converter 242 result about the input axis 206 andthereby cause a change of ratio of the rotational speed of the outputmember 208 relative to the input member 202.

In the instance of the power transmission 200, a housing 258 may besuitably mounted on the input member 202 and on the output member 208and encompass the mechanism describe for its protection, but, unlike theinstance of the embodiment FIGS. 1-3, no interaction occurs between thehousing 258 and the assembly comprising the reaction control rotor 222,the output disk 212 and the pericyclic motion converter.

Yet another embodiment of the invention can be seen with respect toFIGS. 16 and 17 which are generally similar to the construction of FIGS.14 and 15. In this instance, similar components are similarly numberedbut modified by use of the suffix “a”. The modified variable speedtransmission 200 a differs from transmission 200 primarily in theprovision of a pericyclic motion converter 242 a which is of amoderately different construction than the pericyclic motion converter242. More specifically, the pericyclic motion converter 242 a includes aperipheral ring 244 a coplanar and coaxial with the canted cam member234 a and an intermediate ring 246 a coplanar and coaxial with thecanted cam member. As in the earlier described embodiment, bearingelements 250 a between and engaged with first and second bearing tracks238 a, 248 a enable rotation of the intermediate ring about the cantedcam member.

A first plurality of radially extending rearward follower pins 252 a atcircumferentially spaced locations extend between and are integral withthe peripheral ring 244 a and with the intermediate ring 246 a, a loadtransmitting follower member 254 a being rotatably mounted on each ofthe rearward follower pins. In a similar fashion, a second plurality ofradially extending forward follower pins 252 b at circumferentiallyspaced locations extend between and are integral with the peripheralring 244 a and with the intermediate ring 246 a, a load transmittingfollower member 254 b being rotatably mounted on each of the forwardfollower pins 252 b. The first plurality of rearward follower pins 252 aand the second plurality of forward follower pins 252 b lie,respectively, in spaced apart parallel planes. As clearly seen in FIG.17, at any one time, a plurality of the load transmitting followermembers 254 a engage a number of the reaction face cams 230 a along anarcuate reach of the reaction control rotor 222 a even as a plurality ofthe load transmitting follower members 254 b engage a number of theoutput face cams 220 a along an arcuate reach of the output disk 212 aat diametrically opposite locations of the pericyclic motion converter242. In this manner, one set of the load transmitting follower membersalways rotate in one direction while the adjoining set always rotate inthe opposite direction. Thus, the construction of FIGS. 16 and 17 avoidsthe shortcoming of the construction of FIGS. 14 and 15 which requiresthe follower members 254 to instantaneously change direction as theymove out of engagement with the reaction face cams 230 and intoengagement with the output face cams 220, and vice versa.

It should be understood that the foregoing description is onlyillustrative of the invention. Various alternatives and modificationscan be devised by those skilled in the art without departing from theinvention. Accordingly, the present invention is intended to embrace allsuch alternatives, modifications and variances which fall within thescope of the appended claims.

What is claimed is:
 1. A continuously variable speed power transmissioncomprising: an input member rotatable about an input axis including alongitudinally extending drive shaft and a canted cam member fixed onthe drive shaft having a first bearing track and a cam axis coplanarwith the input axis but angularly disposed relative to the input axis;an output member rotatable about an output axis including a plurality ofrearwardly directed output face cams thereon, the output member alsoincluding a longitudinally extending driven shaft, a hub fixed on thedriven shaft, an outer peripheral rim lying in a plane perpendicular tothe output axis and extending between an outer peripheral flange on theouter peripheral rim containing the plurality of rearwardly directedoutput face cams, and a plurality of radially extending spokes atcircumferentially spaced locations extending between and integral withthe hub and with the outer peripheral rim; a reaction control rotormounted for selective rotation about the input axis including aplurality of forwardly directed reaction face cams thereon in oppositionto the output face cams on the output member, the reaction control rotoralso including a hub rotatably mounted on the drive shaft, an outerperipheral rim lying in a plane perpendicular to the input axis andcontaining the plurality of forwardly directed reaction face cams, and aplurality of radially extending spokes at circumferentially spacedlocations extending between and integral with the hub and with the outerperipheral rim; a pericyclic motion converter rotatably mounted fornutational motion about the input axis including a plurality of loadtransmitting follower members thereon simultaneously engageable with theoutput face cams and with the reaction face cams, the pericyclic motionconverter also including a peripheral ring coplanar and coaxial with thecanted cam member, an intermediate ring coplanar and coaxial with thecanted cam member and having a second bearing track spaced from andopposed to the first bearing track, bearing elements between and engagedwith the first and second bearing tracks enabling rotation of theintermediate ring about the canted cam member, and a plurality ofradially extending follower pins at circumferentially spaced locationsextending between and integral with the peripheral ring and with theintermediate ring, a load transmitting follower member being rotatablymounted on each of the follower pins; and control means for selectivelyadjusting the rate of rotation of the reaction control rotor relative tothe input member; whereby relative rotation between the reaction controlrotor and the input member results in both rotation and nutation of thepericyclic motion converter about the input axis and thereby results ina continuously variable change of ratio of the rotational speed of theoutput member relative to the input member.
 2. A continuously variablespeed power transmission as set forth in claim 1 wherein the pluralityof load transmitting follower members includes first load transmittingfollower members engageable with the output face cams and second loadtransmitting follower members engageable with the reaction face cams. 3.A continuously variable speed power transmission comprising: a housing;an input member rotatable about an input axis; an output memberrotatable about an output axis including a plurality of rearwardlydirected output face cams thereon; a reaction control rotor mounted onthe housing for selective rotation about the input axis including aplurality of forwardly directed reaction face cams thereon in oppositionto the rearwardly directed output face cams on the output member; apericyclic motion converter rotatably mounted on the input member fornutational motion about the input axis including a plurality of loadtransmitting follower members thereon simultaneously engageable with theoutput face cams and with the reaction face cams; and control means forselectively adjusting the rate of rotation of the reaction control rotorrelative to the input member; wherein the load transmitting members ofthe pericyclic motion converter kinematically under pure rolling contacttraverse a mathematically higher order spherical path of action duringeach revolution of the input member; whereby relative rotation betweenthe reaction control rotor and the input member results in both rotationand nutation of the pericyclic motion converter about the input axis andthereby results in a continuously variable change of rotational speed ofthe output member relative to the input member.
 4. A continuouslyvariable speed power transmission as set forth in claim 3 wherein theinput member includes a longitudinally extending drive ring; wherein thereaction control rotor includes an input disk lying in a planeperpendicular to the input axis and extending between a hub rotatablymounted on the housing and an outer peripheral flange containing theplurality of forwardly directed reaction face cams; and wherein theoutput member includes a longitudinally extending driven shaft and anintegral output disk lying in a plane perpendicular to the output axisand extending between a hub fixed on the driven shaft and an outerperipheral flange containing the plurality of rearwardly directed outputface cams.
 5. A continuously variable speed power transmission as setforth in claim 4 wherein the drive ring and the driven shaft are axiallyaligned.
 6. A continuously variable speed power transmission as setforth in claim 3 wherein the input member includes a longitudinallyextending drive ring; wherein the reaction control rotor includes a hubrotatably mounted on the housing, a web member lying in a planeperpendicular to the input axis and a peripheral flange containing theplurality of forwardly directed reaction face cams, and a web memberextending between and integral with the hub and with the peripheral rim;and wherein the output member includes a longitudinally extending drivenshaft, a hub fixed on the driven shaft, an outer peripheral flangecontaining the plurality of rearwardly directed output face cams, and aweb member extending between and integral with the hub and with theouter peripheral flange.
 7. A continuously variable speed powertransmission as set forth in claim 6 wherein the drive ring and thedriven shaft are axially aligned.
 8. A continuously variable speed powertransmission as set forth in claim 3 wherein the input member includes alongitudinally extending drive ring having an inner annular surface andan outer annular surface; first bearing elements between the outerannular surface of the drive ring and the housing enabling rotation ofthe drive ring about the input axis; and wherein the pericyclic motionconverter includes: a peripheral ring coaxial with the input axis andlying in a plane canted relative to the input axis; and second bearingelements between the peripheral ring and the inner annular surface ofthe drive ring; an intermediate ring coplanar and coaxial with theperipheral ring spaced therefrom; and a plurality of radially extendingfollower pins at circumferentially spaced locations extending betweenand integral with the peripheral ring and with the intermediate ring, aload transmitting follower member being rotatably mounted on each of thefollower pins.
 9. A continuously variable speed power transmission asset forth in claim 8 wherein the plurality of radially extendingfollower pins includes a first set of follower members lying in a circlelocated at a first radius distant from the input axis and a second setof follower members lying in a circle located at a second radius distantfrom the input axis; and wherein the forwardly directed reaction facecams lie in a circle located at the first radius distant from the inputaxis; and wherein the rearwardly directed output face cams lie in acircle located at the second radius distant from the input axis.
 10. Acontinuously variable speed power transmission as set forth in claim 3wherein the input member includes a longitudinally extending drive ringhaving an inner annular surface and an outer annular surface; including:first bearing elements between the outer annular surface of the drivering and the housing enabling rotation of the drive ring about the inputaxis; and a fixed reaction control rotor mounted on the housingincluding a plurality of rearwardly directed reaction face cams; whereinthe output member includes a plurality of forwardly directed output facecams thereon in opposition to the rearwardly directed reaction face camson the fixed reaction control rotor; wherein the pericyclic motionconverter includes: a first peripheral ring coaxial with the input axisand lying in a plane canted relative to the input axis; a firstintermediate ring coplanar and coaxial with the first peripheral ringand radially spaced therefrom; a plurality of radially extending firstfollower pins at circumferentially spaced locations extending betweenand integral with the first peripheral ring and with the firstintermediate ring, a first load transmitting follower member beingrotatably mounted on each of the first follower pins; a secondperipheral ring coaxial with the input axis and lying in a plane cantedrelative to the input axis; a second intermediate ring coplanar andcoaxial with the second peripheral ring and radially spaced therefrom;and a plurality of radially extending second follower pins atcircumferentially spaced locations extending between and integral withthe second peripheral ring and with the second intermediate ring, a loadtransmitting follower member being rotatably mounted on each of thesecond follower pins; wherein the plane of the first peripheral ring andfirst intermediate ring is angularly disposed relative to the plane ofthe second peripheral ring and second intermediate ring; such that firstload transmitting follower members are engaged with the forwardlydirected reaction face cams as diametrically opposed first loadtransmitting follower members are engaged with the rearwardly directedoutput face cams on the output member; and such that, simultaneously,second load transmitting follower members are engaged with therearwardly directed output face cams on the output member asdiametrically opposed second load transmitting follower members areengaged with the forwardly directed reaction face cams on the firstreaction control rotor.
 11. A continuously variable speed powertransmission as set forth in claim 10 including: a first set of thefollower members lying in a circle located at a first radius distantfrom the input axis and a second set of the follower members lying in acircle located at a second radius distant from the input axis; andwherein the forwardly directed reaction face cams lie in a circlelocated at the first radius distant from the input axis; and wherein therearwardly directed output face cams lie in a circle located at thesecond radius distant from the input axis; and a third set of thefollower members lying in a circle located at a first radius distantfrom the input axis and a fourth set of the follower members lying in acircle located at a second radius distant from the input axis; andwherein the forwardly directed reaction face cams lie in a circlelocated at the second radius distant from the input axis; and whereinthe rearwardly directed output face cams lie in a circle located at thefirst radius distant from the input axis.
 12. A continuously variablespeed power transmission comprising: an input member rotatable about aninput axis including a longitudinally extending drive shaft and a cantedcam member fixed on the drive shaft having a first bearing track and acam axis coplanar with the input axis but angularly disposed relative tothe input axis; an output member rotatable about an output axisincluding a plurality of rearwardly directed output face cams thereon; areaction control rotor mounted for selective rotation about the inputaxis including a plurality of forwardly directed reaction face camsthereon in opposition to the output face cams on the output member; apericyclic motion converter rotatably mounted for nutational motionabout the input axis including a plurality of load transmitting followermembers thereon simultaneously engageable with the output face cams andwith the reaction face cams, the pericyclic motion converter alsoincluding a peripheral ring coplanar and coaxial with the canted cammember, an intermediate ring coplanar and coaxial with the canted cammember and having a second bearing track spaced from and opposed to thefirst bearing track, bearing elements between and engaged with the firstand second bearing tracks enabling rotation of the intermediate ringabout the canted cam member, a first plurality of radially extendingrearward follower pins at circumferentially spaced locations extendingbetween and integral with the peripheral ring and with the intermediatering, a load transmitting follower member being rotatably mounted oneach of the rearward follower pins, and a second plurality of radiallyextending forward follower pins at circumferentially spaced locationsextending between and integral with the peripheral ring and with theintermediate ring, a load transmitting follower member being rotatablymounted on each of the forward follower pins, the first plurality ofrearward follower pins and the second plurality of forward follower pinslying respectively in spaced apart parallel planes; and control meansfor selectively adjusting the rate of rotation of the reaction controlrotor relative to the input member; whereby relative rotation betweenthe reaction control rotor and the input member results in both rotationand nutation of the pericyclic motion converter about the input axis andthereby results in a continuously variable change of ratio of therotational speed of the output member relative to the input member. 13.A continuously variable speed power transmission as set forth in claim12 wherein the reaction control rotor includes a hub rotatably mountedon the drive shaft, an outer peripheral rim lying in a planeperpendicular to the input axis and containing the plurality offorwardly directed reaction face cams, and a plurality of radiallyextending spokes at circumferentially spaced locations extending betweenand integral with the hub and with the outer peripheral rim; and whereinthe output member includes a longitudinally extending driven shaft, ahub fixed on the driven shaft, an outer peripheral rim lying in a planeperpendicular to the output axis and extending between an outerperipheral flange on the outer peripheral rim containing the pluralityof rearwardly directed output face cams, and a plurality of radiallyextending spokes at circumferentially spaced locations extending betweenand integral with the hub and with the outer peripheral rim.
 14. Acontinuously variable speed power transmission comprising: an inputmember rotatable about an input axis including a longitudinallyextending drive shaft and a canted cam member fixed on the drive shafthaving a first bearing track and a cam axis coplanar with the input axisbut angularly disposed relative to the input axis; an output memberrotatable about an output axis including a plurality of rearwardlydirected output face cams thereon; a reaction control rotor mounted forselective rotation about the input axis including a plurality offorwardly directed reaction face cams thereon in opposition to theoutput face cams on the output member; a pericyclic motion converterrotatably mounted for nutational motion about the input axis including aplurality of load transmitting follower members thereon simultaneouslyengageable with the output face cams and with the reaction face cams,the pericyclic motion converter including a peripheral ring coplanar andcoaxial with the canted cam member, an intermediate ring coplanar andcoaxial with the canted cam member and having a second bearing trackspaced from and opposed to the first bearing track, bearing elementsbetween and engaged with the first and second bearing tracks enablingrotation of the intermediate ring about the canted cam member, aplurality of radially extending first follower pins at circumferentiallyspaced locations extending between and integral with the peripheral ringand with the intermediate ring, a first load transmitting followermember being rotatably mounted on each of the first follower pins andengageable with the output face cams, and a plurality of radiallyextending second follower pins at circumferentially spaced locationsextending between and integral with the peripheral ring and with theintermediate ring, a second load transmitting follower member beingrotatably mounted on each of the second follower pins and engageablewith the reaction face cams, the second follower pins lying generally ina plane parallel to and spaced from the first follower pins; and controlmeans for selectively adjusting the rate of rotation of the reactioncontrol rotor relative to the input member; whereby relative rotationbetween the reaction control rotor and the input member results in bothrotation and nutation of the pericyclic motion converter about the inputaxis and thereby results in a continuously variable change of ratio ofthe rotational speed of the output member relative to the input member.15. A continuously variable speed power transmission comprising: aninput member rotatable about an input axis; an output member rotatableabout an output axis including a plurality of rearwardly directed outputface cams thereon; a reaction control rotor mounted for selectiverotation about the input axis including a plurality of forwardlydirected reaction face cams thereon in opposition to the output facecams on the output member; a pericyclic motion converter rotatablymounted for nutational motion about the input axis including a pluralityof load transmitting follower members thereon simultaneously engageablewith the output face cams and with the reaction face cams; and controlmeans for selectively adjusting the rate of rotation of the reactioncontrol rotor relative to the input member; wherein the loadtransmitting members of the pericyclic motion converter kinematicallyunder pure rolling contact traverse a mathematically higher orderspherical path of action during each revolution of the input member;whereby relative rotation between the reaction control rotor and theinput member results in both rotation and nutation of the pericyclicmotion converter about the input axis and thereby results in acontinuously variable change of ratio of the rotational speed of theoutput member relative to the input member.
 16. A continuously variablespeed power transmission as set forth in claim 15 wherein the inputmember includes a longitudinally extending drive shaft; wherein thereaction control rotor includes an input disk lying in a planeperpendicular to the input axis and extending between a hub rotatablymounted on the drive shaft and an outer peripheral flange containing theplurality of forwardly directed reaction face cams; and wherein theoutput member includes a longitudinally extending driven shaft and anintegral output disk lying in a plane perpendicular to the output axisand extending between a hub fixed on the driven shaft and an outerperipheral flange containing the plurality of rearwardly directed outputface cams.
 17. A continuously variable speed power transmission as setforth in claim 16 wherein the drive shaft and the driven shaft areaxially aligned.
 18. A continuously variable speed power transmission asset forth in claim 15 wherein the input member includes a longitudinallyextending drive shaft; wherein the reaction control rotor includes a hubrotatably mounted on the drive shaft, a web member lying in a planeperpendicular to the input axis and a peripheral flange containing theplurality of forwardly directed reaction face cams, and a plurality ofradially extending spokes at circumferentially spaced locationsextending between and integral with the hub and with the peripheral rim;and wherein the output member includes a longitudinally extending drivenshaft, a hub fixed on the driven shaft, an outer peripheral flangecontaining the plurality of rearwardly directed output face cams, and aplurality of radially extending spokes at circumferentially spacedlocations extending between and integral with the hub and with the outerperipheral flange.
 19. A continuously variable speed power transmissionas set forth in claim 18 wherein the drive shaft and the driven shaftare axially aligned.
 20. A continuously variable speed powertransmission as set forth in claim 15 wherein the input member includesa longitudinally extending drive shaft and a canted cam member fixed onthe drive shaft having a first bearing track and a cam axis coplanarwith the input axis but angularly disposed relative to the input axis;and wherein the pericyclic motion converter includes: a peripheral ringcoplanar and coaxial with the canted cam member; an intermediate ringcoplanar and coaxial with the canted cam member and having a secondbearing track spaced from and opposed to the first bearing track;bearing elements between and engaged with the first and second bearingtracks enabling rotation of the intermediate ring about the canted cammember; and a plurality of radially extending follower pins atcircumferentially spaced locations extending between and integral withthe peripheral ring and with the intermediate ring, a load transmittingfollower member being rotatably mounted on each of the follower pins.